The term piston in the context of internal combustion engines denotes a moving component, which together with a fixed component, the so-called cylinder, forms a closed combustion chamber, the volume of which can be varied through movement of the piston in the cylinder. For driving a crankshaft of the internal combustion engine, the crankshaft is connected to the piston by way of a connecting rod. Such a coupling of the connecting rod can be done by means of a piston pin, which is received by a piston-pin boss formed in the piston.
DE 34 25 965 A1 discloses a piston of the generic type for an internal combustion engine having a piston skirt which extends in a piston longitudinal direction and is defined in a piston longitudinal direction by a piston head. Here a boxed interior space, which is defined by two box walls and two substantially opposing skirt walls or skirt wall portions is arranged in the piston skirt. A boss having a through-opening for a piston pin is arranged on each of the two box walls, wherein the two through-openings are oriented so that they align with one another. Here, in the area of the boss, a piston skirt of the known piston, closed at the lower end, is set back from the outer body of the piston, forming a recess on either side of a horizontal piston pin plane, to an extent intended to prevent oil backing up in the recesses.
DE 10 2011 085 448 A1 discloses a further piston, which comprises a piston head having a ring belt and a skirt part, which is arranged on the piston head and comprises at least two load-bearing skirt-wall portions, and wherein the load-bearing skirt-wall portions are connected to one another by at least two obliquely inclined box walls set back in relation to the piston outside diameter. A piston-pin boss is arranged in each box wall to receive a piston pin. The inner face of the piston-pin boss, seen in relation to the piston center, here runs flush with the face of the associated box wall, wherein the box wall has a concave shape in its profile transversely to the direction of the piston-pin boss. This is intended to provide a piston that is lighter in weight but nevertheless inflexible.
One aspect that has proved disadvantageous with all pistons known from the prior art, however, is the noise generated in the operation of the internal combustion engine, caused in particular by the periodic variation in the attitude of the piston in the cylinder liner.